another input cap question for SI t-amp

[schumpe]

Attached is a close up of the board where I made the mods. That's about as good as it gets with my camera.

I also replaced C10 (the first mod I did), but the amp was working fine after this and it doesn't look like anything there has been damaged.

I just wired the new input caps in air to the connector.

I do have a multimeter but it's an old analogue one. It's definitely good enough to check for connectivity and it seems like all the connections are sound.


Thanks again for your help guys, this is too bad, I really liked this little amp. Maybe I'll bite the bullet and buy one of the 41hz boards....

 

[schumpe]

Here is another picture of the amp.
You can see the new input caps on the right, the negative side goes to the pot. Though the input wires from the connectors are very short, they are not in contact with each other.
The cap on the left is the new C10. The red wires go to the switch and the white one with the Xs to signal ground.
That little red bulb under the right alligator clip is the LED.

 

[Lostcause]

it seems like all the connections are sound.

Oh well... if you're sure that everything is oK on the input then I can't see anything else going wrong....
I have replaced quite a few CPUMP caps though when they have blown but I doubt that they are linked... test for continuity across the cap to be sure though?

It's C9 on the old sonic board, not sure about the new one...need a picture...
If you get continuity across it then it's duff......

 

[schumpe]

I know it's weird, it should work unless I actually destroyed the chip or something during my mods....
I checked everything systematically so many times, so I am fairly sure I'm not overlooking anything.
What exactly do you mean by checking for continuity across the cap?

 

[Lostcause]

Check to see if this one is toast...
It's blown on 3 sonics I've repaired over the years...

As per the last tests, check across the cap to see if you get a resistance... ..if it progressively increases to infinity then it's ok...if you get a constant small resistance of anything at all then it's toast
Check it in both polarities, i.e. switch the probes.

send me a PM if you want to discuss this in more detail

 

[schumpe]

My meter shows infinity resistance on C9. When I have some more time, I could check the other caps and resistors on the board as well.
Would the resistance reading guarantee that the cap is still good (I have some lack of knowledge in basic electronics....)?

Are there specific ones which are known to cause problems?
Is there any easy way to check if the chip is still good - probably not, eh?

Thanks for the help! So far I've been able to resolve my issues with the help of the forum, so I won't give up, yet....

 

[Lostcause]

My meter shows infinity resistance on C9. When I have some more time, I could check the other caps and resistors on the board as well.
Would the resistance reading guarantee that the cap is still good (I have some lack of knowledge in basic electronics....)?

Are there specific ones which are known to cause problems?
Is there any easy way to check if the chip is still good - probably not, eh?

Thanks for the help! So far I've been able to resolve my issues with the help of the forum, so I won't give up, yet....

Hmmm, when you say infinity resistance are you saying that there is some resistance?
For it to be OK it should steadily increase in resistance or should get absolutely no reading whatsoever....nada...zip...diddly

 

[Lostcause]

That's on the highest resistance setting by the way.
If you are on the lowest setting then you wont get the progressively increasing steps......the DMM will never read anthing.

Like I said.. e-mail me or turn your private email option on....